Today, network devices that provide services (henceforth called “servers”), such as printing, projecting, display, and file sharing services, need to remain online to respond to requests from client devices (“clients”) that need the services. However, power conservation is also of foremost importance. Furthermore, many devices today are becoming mobile, with wireless network interfaces and limited battery power. These devices need to be able to efficiently search for or advertise their own services without quickly depleting their power supplies. Service advertisement and discovery over a network is typically done using a protocol operating at Layer-3 or a higher layer in the networking stack. Such protocols require the client device that wishes to discover and utilize a service first establish a connection with the network before discovering available services. With wireless networking, if the client is in an environment where there are multiple networks, the client may be forced to connect and then disconnect from multiple networks before identifying the network that provides the required service. This approach is inefficient in terms of time and power consumption.
Thus, a strong need exists for improved techniques for discovering services provided in a wireless networks.
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